The present invention concerns a unique anaerobic sealant composition which is relatively stable prior to curing and a method of producing the same.
Anaerobic sealant systems are those which are stable in the presence of oxygen, but will polymerize in the absence of oxygen. Polymerization is initiated by the presence of a peroxy compound. The cured, cross-linked resins serve as sealants and as adhesives.
Typical resin monomers are terminated with polymerizable acrylate esters such as methacrylate, ethacrylate and chloracrylate esters. Some of the other ingredients typically present are an initiator, preferably an organic hydroperoxide such as cumene hydroperoxide, tertiary butyl hydroperoxide and the like. There is also normally provided a stabilizer against free radical initiation, such as a quinone or hydroquinone, in an amount sufficient to prevent premature polymerization of the adhesive due to decomposition of the peroxy compound. There are also preferably present one or more accelerators which are preferably nitrogen-containing compounds such as tertiary amines, imids, sulfimides and the like which promote the rate of cure. In addition to the foregoing, various other additives are often used to accomplish certain other purposes.
One of the many known commercially acceptable anaerobic compositions is set forth in U.S. Pat. No. 2,895,950 to Krieble, issued July 21, 1959. Other typical disclosures of related or improved anaerobic compositions may be found, for example, in U.S. Pat. Nos. 3,043,820 to Krieble, issued July 10, 1962; 3,046,262 to Krieble, issued July 24, 1962, 3,218,305 to Krieble, issued Nov. 16, 1975; and 3,435,012 to Nordlander, issued Mar. 25, 1969.
While the foregoing patents all disclose anaerobic sealant compositions having certain desirable properties, no teaching can be found in any of them which provides an anaerobic sealant composition which prior to polymerizing is stable for long periods of time, i.e., will not separate into its individual component parts upon standing for an extended period of time.
Accordingly, it is the principal object of the present invention to provide an anaerobic sealant composition which upon standing for an extended period of time will not separate into a plurality of phases.
In addition, another object of the invention is to provide an anaerobic sealant composition which when polymerized forms a solidified sealant mass which is relatively non-brittle.
The above-recited and other objects of the invention will become clear to those skilled in the art from a reading of the following specification and claims.